Make sure to play a campaign map first so that the Left 4 Bots 2 addon can generate an ems folder for you to edit the txt files in it. If you have already downloaded the addon before the update on 15 Feb 2025, delete the said ems folder (titled "left4bots2") before following the said instruction. I strongly suggest using Notepad++ (Google it) for editing since Microsoft Notepad might incorrectly display the commands in the files. In addition, remove all other addons that alter the AI of the survivor bots if you notice your survivor bots acting weirdly after installing L4B2 (including the original Left 4 Bots addon if any).



Go to...

SteamLibrary\steamapps\common\Left 4 Dead 2\left4dead2\ems\left4bots2\cfg\weapons

This is where you can change the weapon preference of your survivor bots so they will pick up items based on the order of priority you have personally set for your bots. For an optimal experience, I would recommend that you replace the default setting of the files with the settings I have written below for each of the survivor bots respectively. These fix the issues of bots picking up the CS Scout and CS AWP as tier 2 weapons (I have shifted it to the tier 1 category) while keeping the survivor bots weapon preference lore-friendly in the context of the Left 4 Dead universe.


Bill

rifle,rifle_ak47,rifle_sg552,rifle_desert,shotgun_spas,autoshotgun,sniper_military,hunting_rifle,smg_mp5,smg_silenced,smg,shotgun_chrome,pumpshotgun,sniper_awp,sniper_scout,rifle_m60,grenade_launcher
pistol_magnum,pistol,machete,knife,katana,golfclub,baseball_bat,fireaxe,chainsaw,cricket_bat,electric_guitar,tonfa,shovel,frying_pan,crowbar,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Coach

shotgun_spas,autoshotgun,hunting_rifle,sniper_military,rifle,rifle_ak47,rifle_sg552,rifle_desert,shotgun_chrome,pumpshotgun,sniper_scout,sniper_awp,smg,smg_silenced,smg_mp5,rifle_m60,grenade_launcher
pistol,pistol_magnum,chainsaw,frying_pan,katana,machete,golfclub,baseball_bat,knife,fireaxe,cricket_bat,electric_guitar,tonfa,shovel,crowbar,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Ellis

sniper_military,hunting_rifle,rifle_sg552,rifle_desert,rifle_ak47,rifle,shotgun_spas,autoshotgun,sniper_awp,sniper_scout,smg_mp5,smg_silenced,smg,shotgun_chrome,pumpshotgun,rifle_m60,grenade_launcher
pistol,pistol_magnum,electric_guitar,pitchfork,katana,machete,golfclub,baseball_bat,knife,fireaxe,chainsaw,cricket_bat,tonfa,shovel,frying_pan,crowbar,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Francis

autoshotgun,shotgun_spas,sniper_military,hunting_rifle,rifle_ak47,rifle,rifle_desert,rifle_sg552,pumpshotgun,shotgun_chrome,sniper_awp,sniper_scout,smg_silenced,smg,smg_mp5,rifle_m60,grenade_launcher
pistol,pistol_magnum,chainsaw,crowbar,katana,machete,golfclub,baseball_bat,knife,fireaxe,cricket_bat,electric_guitar,tonfa,shovel,frying_pan,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Louis

rifle_sg552,rifle_desert,rifle_ak47,rifle,shotgun_spas,autoshotgun,hunting_rifle,sniper_military,smg,smg_silenced,smg_mp5,shotgun_chrome,pumpshotgun,sniper_scout,sniper_awp,rifle_m60,grenade_launcher
pistol_magnum,pistol,tonfa,riotshield,katana,machete,golfclub,baseball_bat,knife,fireaxe,chainsaw,cricket_bat,electric_guitar,shovel,frying_pan,crowbar,pitchfork
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Nick

rifle_ak47,rifle,rifle_desert,rifle_sg552,autoshotgun,shotgun_spas,sniper_military,hunting_rifle,smg_silenced,smg,smg_mp5,pumpshotgun,shotgun_chrome,sniper_awp,sniper_scout,rifle_m60,grenade_launcher
pistol_magnum,pistol,golfclub,baseball_bat,katana,machete,knife,fireaxe,chainsaw,cricket_bat,electric_guitar,tonfa,shovel,frying_pan,crowbar,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Rochelle

rifle_desert,rifle_sg552,rifle,rifle_ak47,autoshotgun,shotgun_spas,hunting_rifle,sniper_military,smg_mp5,smg,smg_silenced,pumpshotgun,shotgun_chrome,sniper_scout,sniper_awp,rifle_m60,grenade_launcher
pistol_magnum,pistol,fireaxe,shovel,katana,machete,golfclub,baseball_bat,knife,chainsaw,cricket_bat,electric_guitar,tonfa,frying_pan,crowbar,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


Zoey

hunting_rifle,sniper_military,rifle_desert,rifle_sg552,rifle,rifle_ak47,autoshotgun,shotgun_spas,sniper_scout,sniper_awp,smg_mp5,smg,smg_silenced,pumpshotgun,shotgun_chrome,rifle_m60,grenade_launcher
pistol,pistol_magnum,katana,cricket_bat,machete,golfclub,baseball_bat,knife,fireaxe,chainsaw,electric_guitar,tonfa,shovel,frying_pan,crowbar,pitchfork,riotshield
molotov,pipe_bomb,vomitjar
first_aid_kit,defibrillator,upgradepack_explosive,upgradepack_incendiary
pain_pills,adrenaline


After modifying and saving the txt files, you will need to copy and paste the said txt files into the "c6m3_port" folder located in the same directory already mentioned. Make sure that your txt files overwrite the txt files in the folder. Otherwise, the survivor bots will default to their original weapon preference in the last level of "The Passing" campaign.



Go to...

SteamLibrary\steamapps\common\Left 4 Dead 2\left4dead2\ems\left4bots2\cfg

Locate the file titled "settings.txt". This is where you will adjust how will survivor bots behave and react in the game. For an optimal experience, copy and paste the commands below into the "settings.txt" file, thus, replacing all the default commands in it.


anti_pipebomb_bug = 1
automation = 1
automation_autostart = 0
automation_debug = 0
automation_stay_in_end_saferoom = 0
bot_think_interval = -1
carry_debug = 0
chat_bg_chance = 100
chat_bg_lines = "bg,cheater,hack,ihatemylife,nooo,reported,vacbanplz,why"
chat_gg_chance = 100
chat_gg_lines = "ggez,ggnore,ggs,ggwp,gitgud,glhf,gm,yesss"
chat_hello_chance = 100
chat_hello_replies = "hello,ahoj,annyeonghaseyo,bonjour,bunaziua,ciao,czesc,hallo,hei,hej,hola,konnichiwa,kumusta,marhaban,merhaba,nihao,ola,privet,pryvit,sawasdeekhap,selamat,szia,xinchao,yassou,zdrasti"
chat_hello_triggers = "hi,hello,hey,hi guys,hi all,hey guys,wassup,yo"
close_saferoom_door = 1
close_saferoom_door_all_chance = 0
close_saferoom_door_behind_range = 1000
close_saferoom_door_distance = 100
close_saferoom_door_highres = 0
damage_barricade = 1
damage_other = 0
deads_scan_defibradius = 250
deads_scan_maxaltdiff = 320
deads_scan_radius = 2000
deploy_upgrades = 1
die_humans_alive = 1
dodge_charger = 1
dodge_charger_diffangle = 10
dodge_charger_distdelay_factor = 0.0006
dodge_charger_maxdistance = 600
dodge_charger_mindistance = 80
dodge_rock = 1
dodge_rock_diffangle = 8
dodge_rock_maxdistance = 600
dodge_rock_mindistance = 140
dodge_spit = 1
dodge_spit_radius = 300
door_failsafe_delay = 0.15
fall_velocity_warp = 560
file_convars = "left4bots2/cfg/convars.txt"
file_itemstoavoid = "left4bots2/cfg/itemstoavoid.txt"
file_vocalizer = "left4bots2/cfg/vocalizer.txt"
file_weapons_prefix = "left4bots2/cfg/weapons/"
follow_pause_radius = 220
give_bots_medkits = 1
give_bots_nades = 1
give_bots_pills = 1
give_bots_upgrades = 1
give_bots_weapons = 1
give_humans_meds = 1
give_humans_nades = 1
give_max_range = 270
handle_l4d1_survivors = 2
heal_force = 0
heal_interrupt_minhealth = 39
heal_spare_medkits_radius = 500
horde_nades_chance = 100
horde_nades_maxaltdiff = 120
horde_nades_radius = 450
horde_nades_size = 10
hurry_time = 180
incap_block_nav_radius = 100
incap_block_nav_tank_range = 2000
items_not_to_avoid = 1
jockey_redirect_damage = 100
lead_check_ground = 0
lead_debug_duration = 0
lead_detour_maxdist = 10000
lead_dontstop_ondamaging = 1
lead_max_segment = 800
lead_max_separation = 0
lead_min_segment = 100
lead_pause_behind_dist = 0
lead_vocalize_interval = 50
load_convars = 1
loglevel = 3
manual_attack_always = 1
manual_attack_common_head_radius = 2000
manual_attack_dual_pistol_nerf = 0
manual_attack_mindot = -1
manual_attack_radius = 2000
manual_attack_saccade_speed = 2000
manual_attack_special_head_radius = 2000
manual_attack_wandering = 0
move_end_radius = 30
move_end_radius_defib = 80
move_end_radius_door = 100
move_end_radius_follow = 100
move_end_radius_heal = 80
move_end_radius_lead = 110
move_end_radius_pour = 16
move_end_radius_scavenge = 80
move_end_radius_wait = 150
move_end_radius_witch = 55
move_hipri_timeout = 5
move_wait_time = 0.5
moveto_debug_duration = 0
moveto_nav = 1
orders_debug = 0
orders_no_queue = 0
pause_debug = 0
pause_min_time = 2
pickups_failsafe_delay = 0.15
pickups_max_separation = 800
pickups_melee_noprimary = 1
pickups_min_interval = 0.8
pickups_pick_range = 90
pickups_pistol_dual = 1
pickups_scan_radius = 400
pickups_wep_always = 1
pickups_wep_ammo_replenish = 80
pickups_wep_min_ammo = 1
pickups_wep_replace_ammo = 1
pickups_wep_upgraded_ammo = 1
play_sounds = 1
scavenge_campaign_autostart = 1
scavenge_drop_radius = 200
scavenge_items_farthest_first = 0
scavenge_items_flow_distance = 1
scavenge_items_from_pourtarget = 0
scavenge_manager_interval = 1
scavenge_max_autofollow = 2
scavenge_max_bots = 1
scavenge_pour = 1
scavenge_usetarget_debug = 0
shoot_rock = 1
shoot_rock_ahead = 4
shoot_rock_diffangle = 8
should_hurry = 1
shove_commons_deltapitch = -6
shove_commons_radius = 35
shove_deadstop_chance = 100
shove_deadstop_deltapitch = -9.5
shove_specials_deltapitch = -6
shove_specials_radius = 70
shove_tonguevictim_deltapitch = -6
shove_tonguevictim_radius = 90
signal_chat = 0
signal_max_distance = 2500
signal_min_distance = 150
signal_min_interval = 5
signal_ping = 0
smart_use_carry = 1
smart_use_deploy = 1
smart_use_destroy = 1
smart_use_scavenge = 1
smoker_shoot_tongue = 1
smoker_shoot_tongue_duck = 0
spit_block_nav = 0
spit_damage_multiplier = 1
stuck_debug = 0
stuck_detection = 1
stuck_nomove_unstuck = 1
stuck_range = 100
stuck_time = 3
t3_ammo_bots = 1
t3_ammo_human = 1
tank_molotov_chance = 100
tank_retreat_radius = 650
tank_throw_deltapitch = 3
tank_throw_min_health = 1
tank_throw_range_max = 1300
tank_throw_range_min = 200
tank_throw_survivors_mindistance = 240
tank_vomitjar_chance = 0
team_max_chainsaws = 8
team_max_melee = 8
team_min_defibs = 0
team_min_medkits = 0
team_min_molotovs = 0
team_min_pipebombs = 0
team_min_shotguns = 0
team_min_vomitjars = 0
thinkers_think_interval = -1
throw_molotov = 1
throw_molotov_interval = 5
throw_nade_deltapitch = -6
throw_nade_interval = 10
throw_nade_mindistance = 250
throw_nade_radius = 500
throw_pipebomb = 1
throw_vomitjar = 1
tracemask_others = 1174421507
tracemask_pickups = 134242379
trigger_caralarm = 0
trigger_witch = 0
userlevel_give_medkit = 1
userlevel_give_others = 0
userlevel_give_weapons = 1
userlevel_orders = 1
userlevel_vocalizer = 0
vocalize_botselect_timeout = 4
vocalizer_commands = 1
vocalizer_goto_stop = "PlayerAnswerLostCall,PlayerLostCall"
vocalizer_laugh_chance = 100
vocalizer_lead_start = "PlayerFollowMe,PlayerMoveOn,PlayerEmphaticGo"
vocalizer_lead_stop = "PlayerAnswerLostCall,PlayerLostCall,PlayerStayTogether,PlayerLeadOn"
vocalizer_onpause_horde_chance = 100
vocalizer_onpause_special_chance = 100
vocalizer_onpause_tank_chance = 100
vocalizer_onpause_witch_chance = 100
vocalizer_sorry_chance = 100
vocalizer_thanks_chance = 100
vocalizer_yes = "PlayerYes,SurvivorBotYesReady"
vocalizer_youwelcome_chance = 100
wait_crouch = 1
wait_nopause = 1
witch_autocrown = 1


This settings above will make the bots react much more quickly to aggressive zombies running toward your general direction, as well as protecting you from most special infected that are planning to ambush you. Do note that this setting above is compatible with the sourcemod All 8 Survivors Sourcemod 2018-2025 addon in the Steam workshop if you wish to play with 8 survivor bots. I would not suggest using any other addon that implement the 8 survivor bots feature since its might cause the L4B2 addon to break in some inexplicable way.

I highly recommend installing this addon Bot Primary Weapon Enforcer. This addon will force the survivor bot to stick to its primary weapon without switching to its secondary weapon, that is until the bots runs out of ammo. In other words, this turn sniper-wielding Ellis and Zoey from worst bots to best bots as they no longer switch to their pistols randomly at the worst possible time. I also recommend installing this addon ion's Vocalizer so that you have an arsenal of vocal commands that you can use to order survivors bots around. Lastly, if you have a persistent issue of survivor bots getting in your line of fire during a firefight, consider installing this addon No Friendly Fire! so as to disable friendly fire entirely.

Locate the file titled "convars.txt" located in the same directory I already mentioned and replace the commands inside it with the commands below...


allow_all_bot_survivor_team 1
sb_all_bot_game 1
sb_enforce_proximity_range 999999
sb_separation_danger_max_range 300
sb_separation_danger_min_range 100
sb_separation_range 300


This will ensure that the survivor bots will not magically teleport to your location when you command bots to wait and you are far away from them. In addition, survivor bots will also follow you closely without straying too far off from you.

For the rest of the files in the "cfg" folder (except vocalizer.txt), delete all the commands before saving the files (Yes, that mean the content of the files must be completely empty). These will ensure that bots aren't prohibited from picking up the items as delineated in your weapon preference files (itemstoavoid.txt is responsible for causing this issue to occur), while making sure that the other settings files do not interfere with the behavior of the survivor bots in any matter. Specifically, these are the files below you should look out for...

• itemstoavoid.txt
  
• settings_c1m4_atrium.txt
  
• settings_c1m4_atrium_hard.txt
  
• settings_c1m4_atrium_impossible.txt
  
• settings_c6m1_riverbank.txt
  
• settings_c6m2_bedlam.txt
  
• settings_c6m3_port.txt
  
• settings_c6m3_port_hard.txt
  
• settings_c6m3_port_impossible.txt
  
• settings_hard.txt
  
• settings_impossible.txt

You are now ready to enjoy Left 4 Dead 2 the way it meant to be played :)